Intel Extensible Firmware Interface - Manual (Page 795)

EFI Byte Code Virtual Machine
Version 1.10 12/01/02 19-21
Table 19-14 CMP Instruction Encoding
BYTE DESCRIPTION
Bit Description
7 0 = Immediate/index data absent
1 = Immediate/index data present
6 0 = 32-bit comparison
1 = 64-bit comparison
Opcode
0
0..5
0x05 = CMPeq compare equal
0x06 = CMPlte compare signed less then/equal
0x07 = CMPgte compare signed greater than/equal
0x08 = CMPulte compare unsigned less than/equal
0x09 = CMPugte compare unsigned greater than/equal
Bit Description
7 0 = Operand 2 direct
1 = Operand 2 indirect
4..6 Operand 2
3 Reserved = 0
1
0..2 Operand 1
2..3 Optional 16-bit immediate data/index
BEHAVIORS AND RESTRICTIONS:
• If Operand 2 is indirect, then the immediate data is interpreted as an index, and the Operand 2
value is fetched from memory address [R
2
+ Index16].
• If Operand 2 is direct, then the immediate data is considered a signed immediate value and is
added to the register contents such that Operand 2 = R
2
+ Immed16.
• Only register direct is supported for Operand 1.